Furnace for electroslag melting of metal ingots

ABSTRACT

A furnace for the electroslag melting of metal ingots, comprising stringers to which are mounted the carriages of the electrode holders with consumable electrodes being remelted into an ingot which is shaped in a cooled mould, the carriages being allowed to transfer vertically. According to the invention secured to the sides of the adjacent electrode holders which face each other are current-carrying plates forming a &#39;&#39;&#39;&#39;seat&#39;&#39;&#39;&#39; for holding in place an additional consumable electrode, and the vertical transfer drives of the electrode holder carriages are aligned axially and face each other with the free ends of their shafts on which half-couplings are engageably mounted. Such a furnace is suitable for melting both large-size ingots and those in a medium and small weight range.

United States Patent Paton et al.

FURNACE FOR ELECTROSLAG MELTING OF METAL INGOTS Inventors: Boris E. Paton, ulitsa Filed:

Izrailevich Medovar, ulitsa A. Barbjusa, 22/26, kv. 109; Jury Fedorovich Alferov, bulvar Lepse, 29, kv. 64;Grigory Bentsionovich Schupak, ulitsa Chudn0vskog0,7, kv.61; Alexei Georgievich Bogachenko, ulitsa Miljutenko, 15/2, kv. 141; Oleg Petrovich Bondarenko, ulitsa Kreschatik, 15,

kv. 36; Vladimir Yakolevich Saenk0,

Kharkouskoe shosse, l8, kv. 71; Anatoly Konstantinovich Tsykulenko, ulitsa Babushkina 23, kv. 38, all of Kiev, U.S.S.R.

Oct. 25, 1973 Appl. No.: 409,447

Foreign Application Priority Data References Cited UNITED STATES PATENTS 3,614,285 10/1971 Holzgruberet al. 13/14 3,660,584 5/1972 Holzgruber et a]. 13 14 3,781,935 1/1974 Medovarl 13/14 Primary Examiner-R. N. Envall Attorney, Agent, or FirmI-lolman & Stern 5 7 ABSTRACT A furnace for the electroslag melting of metal ingots, comprising stringers to which are mounted the carriages of the electrode holders with consumable electrodes being remelted into an ingot which is shaped in a cooled mould, the carriages being allowed to transfer vertically. According to the invention secured to the sides of the adjacent electrode holders which face each other are current-carrying plates forming a seat for holding in place an additional consumable electrode, and the vertical transfer drives of the electrode holder carriages are aligned axially and face each other with the free ends of their shafts on which Apr. 28, 1973 U.S.S.R l904603 halficouplings are engageably mounted Such a nace is suitable for melting both large-size ingots and US. Cl. 13/14, 13/16 those in a medium and Small weight range. Int. Cl. H05b 7/12 Field of Search 13/14 17 4 Claims, 7 Drawing Figures lllll IE1 1||1|| /4 U 15 T'l f5 11 -----/0 um um 3,839,591 mimm sum ear 4 SHEET 3 BF 4 PATENTEDnm I 1914 BACKGROUND OF THE INVENTION The present invention relates to furnaces for the electroslag melting of metal ingots employed in electrometallurgy, preferably for melting ingots to be further rolled into sheets the ingots being referred to hereinafter as slab ingots.

A furnace for the electroslag melting of metal ingots is known in the prior art, comprising at least a pair of stringers with electric holder carriages fastened thereto, the carriages being furnished with drives for vertical transfer of consumable electrodes remelted into the ingot which is shaped in a cooled mould.

However, technological possibilities of the melting process effected in the known furnaces are often limited due to the absence of the requisite number of the electrode holders and inadequate number of the degrees of freedom they possess. It is particularly true for the furnaces adapted for melting slab ingots.

The above furnaces are employed for remelting one or two consumable electrodes according to electrodebase plate and electrode-electrode" circuits.

Lately a need has arisen for the electroslag furnaces adapted for melting heavy slab ingots up to 80 t. in weight. Simultaneously it is desirable that one and the same furnace should be used for melting both large-size slab ingots and those in medium and small typesizes from 5 to t. upwards in weight.

The production of such a wide range of high-grade ingots calls firstly for different number of electrodes to be used in melting each slab ingot and, secondly, for different technique in feeding them into a cooled mould. Moreover, in melting superheavy ingots in order to provide more uniform distribution of heat introduced by the consumable electrodes into a slag and, hence, a metal bath, it is desirable to ensure an electrode transfer along the slag bath as well.

In addition, in melting ingots in medium and small type-sizes it would be desirable that the furnace efficiency would not drop markedly.

SUMMARY OF THE INVENTION The principal object of the invention is the provision of a furnace for electroslag melting of metal ingots which will provide for the melting of both large-size slab ingots and those in a medium and small weight range.

Another, but no less important, object of the invention is to provide a furnace which will be capable of operating concurrently with a single or a plurality of electrode holders when using one or several cooled moulds.

Still another object of the invention is the provision of a possibility of holding in place additional electrodes to be arranged intermediate of the adjacent electrode holders of the furnace.

The main object of the present invention is to provide for the transfer of the electrode holders in a horizontal direction for mounting the consumable electrodes of different cross-sections therebetween as well as the possibility of carrying the consumable electrodes along the slag bath when melting ingots by feeding the electrodes with the help of two electrode holders into a single common mould.

These and other objects of the invention are achieved by the provision of a furnace for the electroslag melting of metal ingots. comprising at least a pair of stringers with electrode holder carriages secured thereto and furnished with drives adapted for vertical transfer of both the carriages and consumable electrodes to be remelted into the ingot being shaped in a cooled mould, which furnace, according to the invention, is fitted with current-carrying plates fastened to the sides of the adl0 joining electrode holders facing each other with the plates forming a seat for holding in place at least one additional consumable electrode, with the drives adapted for vertical transfer of the electrode holder carriages being aligned axially and facing each other with the free ends of their shafts on which engageable halfcouplings are mounted.

The above furnace furnished with at least two electrode holders with the current-carrying plates fastened to the electrode holders, and with the drives arranged appropriately and fitted with the half-couplings ensure the melting of slab ingots up to t. in weight without any noticeable decrease in the furnace efficiency when changing over to the melting of the ingots of any other typesize, providing in the meantime an optimum for the particular ingot fiowsheet.

The presence of the seat located intermediate of the two electrode holders, and of the half-couplings mounted on the output drive shafts of the electrode holder carriages enables the total capacity of the drives to be utilized for the melting, according to an electrode-electrode and electrode-base plate circuit, of the entire range of the ingots exceeding in weight those melted out with the aid of a single electrode holder.

It is expedient that each carriage mount horizontal slide-ways with the electrode holders installed therein and be fitted with additional drives adapted to carry the electrode holders along the slideways.

The transfer of the electrode holders with the current-carrying plates in a horizontal direction allows anchoringthe consumable electrodes of different crosssection at the seat and carrying them along the slag bath during the melting process simultaneously with the electrodes fastened to the adjoining electrode holders.

The furnace can be equipped with carriages for the cooled moulds, each carriage being mounted on a corresponding stringer and fitted with a vertical transfer drive aligned axially and facing each other with the free ends of their shafts on which the half-couplings are engageably mounted.

Due to this, the total capacity of the two mould transfer drives can be used for melting the slab ingots superior in weight to those which could have been melted by making use of the capacity of a single drive.

It is desirable that a single common mould be mounted on the carriages for melting the consumable electrodes secured in several electrode holders. This will make it possible to melt ingots exceeding in their weight and volume those which could have been melted individually in the moulds set up on each carriage.

BRIEF DESCRIPTION OF THE DRAWINGS The invention is further exemplified by a detailed description of exemplary embodiments of the furnace, to be had in conjunction with the accompanying drawings, wherein:

FIG. 1 shows a front view of the furnace with two electrode holders whose engageable drives serve to hold in place an additional consumable electrode arranged in a seat located intermediate of the above electrode holders;

FIG. 2 is a section view taken along the line "-11 of FIG. 1;

FIG. 3 depicts a front view of the furnace with the electrode holders between which a consumable electrode of considerable dimensions is positioned;

FIG. 4 is a front view of the furnace with the extreme and central electrode holders mounting the consumable electrodes held in place by the combined drives;

FIG. 5 is a front view of a furnace with the extreme electrode holders carrying the consumable electrodes;

FIG. 6 shows a front view of a furnace with the electrode holder carriage drives disengaged for melting ingots alternately in different moulds and;

FIG. 7 is a back view of a furnace with the drives of the electrode holder carriages and moulds furnished with halfcouplings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A furnace for the electroslag melting of ingots 1 (FIG. 1) comprises two stringers 2 and 3 with each of them mounting a single carriage 4 and 5 in such a manner that they are capable of moving along the appropriate stringer.

Drives 6 and 7 for vertical transfer of the carriages 4 and 5 of the electrode holders 8 and 9 are aligned axially and face each other with the free ends of shafts 10 and 11 with half-couplings 12 and 13 being held 'to each shaft.

Each carriage 4 and 5 carries horizontal slideways 14 and 15, 16 and 17 (FIG. 2) in which the electrode holders 8 and 9 (FIG. 1) are mounted. The carriages 4 and 5 are fitted with additional drives 18 and 19 adapted to transfer the electrode holders 8 and 9 in the abovementioned horizontal slideways.

Fastened to the sides of the adjacent electrode hold- I ers 8 and 9 facing one another are current-carrying plates 20 and 21 forming a seat to accommodate at least a single additional consumable electrode 22 located intermediate of consumable electrodes 23 and 24 clamped in the electrode holders 8 and 9.

In the bottom portion of the furnace provision is made for a carriage 25 with a base plate 26 on which a cooled mould 27 is set up before the process of melting the ingot is initiated. In the course of melting of the consumable electrodes, the top part of the ingot incorporates a metal bath 28 above which a slag bath 29 is located.

Where the consumable electrode 30 (FIG. 3) being remelted has considerable dimensions, it can be positioned intermediate of the electrode holders 8 and 9 anchored at the carriages 4 and 5 with the engageable drives 6 and 7. The cooled mould 27 can be mounted on carriages 31 and 32 (FIG. 7), each one of the carriages being set up on the appropriate stringer 2 and 3, so as to allow its transfer along the stringer. In order to enable concurrent transfer of the carriages 31 and 32, their drives 33 and 34 are aligned axially and fitted with half-couplings 35 and 36 put on the free ends of shafts 37 and 38 facing each other.

In order to melt the ingots into individual moulds with the electrode holders 8 and 9 (FIG. 6) moving independently. the half-couplings l2 and 13 (FIG. 6) of the drives 6 and 7 of the carriages 4 and 5 of the electrode holders 8 and 9 and half-couplings 35 and 36 (FIG. 7) of the drives 33 and 34 of the mould carriages 31 and 32 should be disengaged.

The consumable electrodes 23 and 24 (FIG. 5) can be attached to the electrode holders 8 and 9 with the half-couplings 12 and 13 being disengaged.

According to another version one of the consumable electrodes 24 (FIG. 4) is clamped in the electrode holder 9 and the other one in the seat formed by the current-carrying plates 20 and 21 fastened to the sides of the adjoining electrode holders 8 and 9.

When an additional consumable electrode 22 or 30 must be anchored at the seat" or when it is desirable to transfer the consumable electrodes along the wide wall of the cooled mould 27, the drives 18 and 19 ensure relative motion of the electrode holders 8 and 9 in a horizontal direction.

The furnace operates in the following manner.

The base plate 26 is set up on the carriage 25 (FIG. 1) for the rolling off of the ingots, with the cooled mould 27 being set up on the base plate 26. Next a slag bath 29 is established.

An electric current is passed from a current supply source (not shown in the drawing) to consumable electrodes 22-24. In this case the half-couplings 12 and 13 of the drives 6 and 7 of the electrode holders 8 and 9 as well as the half-couplings 35 and 36 of the drives 33 and 34 of the carriages 31 and 32 of the mould 27 are engaged and an additional electrode 22 is arranged intermediate of the extreme electrode holders 8 and 9. Thus, three pairs of electrodes are melted in the common mould 27. Due to liberation of heat in the slag bath 29, the consumable electrodes 22-24 melt off forming a metal bath 28 under which an ingot 1 crystallizes. With the above method, a large-size metal ingot can be built-up.

A similar large-size ingot 1 can be melted by using one pair of consumable electrodes 30 (FIG. 3) having a rather large cross-section. The electrodes can be attached between the two electrode holders 8 and 9 by using the total capacity of the drives 6 and 7 with the engaged half-couplings l2 and 13.

For securing such consumable electrodes 30, the electrode holders 8 and 9 are separated by the drives 18 and 19 to provide a requisite spacing therebetween.

A large-size ingot 1 (FIG. 4) can be also melted with one of the consumable electrodes being attached in one of the extreme electrode holders and the other one arranged between the current-carrying plates of the electrode holders. It is expedient to use this version for melting heavy ingots with a relatively small crosssection.

As to the ingots in a medium and small weight range, they are melted by using the capacity of each drive (mounted on each stringer) individually. If that is the case, the half-couplings l2 and 12 (FIGS. 5 and 6) are disengaged. For carrying out the melting process, use is made of two carriages with the base plates mounted each under the appropriate mould, with the electrodes being in that case fed into the moulds and remelted therein independently.

In this case both the independent feed of the consumable electrodes and their horizontal transfer are effected in the slag bath of a single common mould supported by two carriages whose drives are engaged with their half-couplings 12 and 13 (FIG. 4) whereas the half-couplings 35 (FIG. 7) of the drives 33 and 34 of the electrode holders 8 and 9 can be disengaged in case the additional consumable electrode 2 is not used.

All the exemplary embodiments disclosed hereinbefore indicate that the furnace is characterized by high versatility and offers a great number of technological combinations in carrying out the electroslag remelting of metals and alloys. Moreover, it affords the possiblity of melting ingots both in heavy and medium and small weight ranges.

What we claim is:

ll. A furnace for the electroslag melting of metal ingots, comprising: at least a pair of stringers; a carriage mounted for vertical transfer on each of said stringers; electrode holders disposed on each of said carriages; current-carrying plates fastened to the sides of said electrode holders facing each other, said currentcarrying plates forming a seat for holding in place at least one additional consumable electrode; drive means for transferring said carriages along said stringers said drive means being aligned axially with the free ends of their shafts facing each other; and half-couplings mounted on each of said drive shafts so as to allow interaction therebetween.

2. A furnace as claimed in claim ll, wherein each of said carriages includes horizontal slideways in which said electrode holders are installed and wherein additional drive means for transferring said electrode holders in said slide ways are provided.

3. A furnace as claimed in claim 1, wherein said stringers carry additional carriages for cooled moulds having vertical transfer drive means which are aligned axially and which face each other with the free ends of their shafts upon which half-couplings are engageably disposed.

4. A furnace as claimed in claim 3, wherein a single common cooled mould for melting consummable elec trodes secured in a plurality of said electrode holders is mounted on said additional carriages. 

1. A furnace for the electroslag melting of metal ingots, comprising: at least a pair of stringers; a carriage mounted for vertical transfer on each of said stringers; electrode holders disposed on each of said carriages; current-carrying plates fastened to the sides of said electrode holders facing each other, said current-carrying plates forming a seat for holding in place at least one additional consumable electrode; drive means for transferring said carriages along sAid stringers, said drive means being aligned axially with the free ends of their shafts facing each other; and half-couplings mounted on each of said drive shafts so as to allow interaction therebetween.
 2. A furnace as claimed in claim 1, wherein each of said carriages includes horizontal slideways in which said electrode holders are installed and wherein additional drive means for transferring said electrode holders in said slide ways are provided.
 3. A furnace as claimed in claim 1, wherein said stringers carry additional carriages for cooled moulds having vertical transfer drive means which are aligned axially and which face each other with the free ends of their shafts upon which half-couplings are engageably disposed.
 4. A furnace as claimed in claim 3, wherein a single common cooled mould for melting consummable electrodes secured in a plurality of said electrode holders is mounted on said additional carriages. 